Cost of debt: new issuance vs. outstanding debt

I’m working on two problems involving WACC. One finds the cost of debt using outstanding debt, while the other, it seems bases it’s cost of debt on a new issuance.

The following problem uses outstanding debt to calculate the YTM (i.e. cost of debt):

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The next problem reads as follows:

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The answer is 7% * (1-40%) = 4.2% while I thought it would have been the average of the two YTMs (8%). Why does the first problem use outstanding debt while the second seemingly uses the current issuance?

Thanks!